1. Field of the Invention
The present invention relates to image processing, and, in particular, to a method and apparatus for locating and decoding bar code symbols in pixel images.
2. Statement of Related Art
Reading bar code symbols with one-dimensional laser scanning systems is well known. Less well known are image processing systems for locating and decoding bar code symbols in two-dimensional pixel images. Decoding bar code symbols requires accurate measurement of edge-to-edge distances, where an edge corresponds to a transition from a bar to a space or from a space to a bar within a bar code symbol.
Of particular difficulty is the reading of high-density bar code symbols in facsimile-quality images, that is, images of bar code symbols generated by facsimile machines and the like. A bar code reader that can locate and decode bar code symbols in an image generated by a facsimile machine should be able to be adapted to read bar code symbols in an image generated by any other image source such as a scanner or a camera.